一种低频外露机载天线隐身设计

针对低成本准隐身飞机,探讨了一种低频外露机载天线的隐身设计,提出了一系列的隐身设计措施(例如优化天线外形、改变安装方式、在天线罩表面涂敷吸波材料等);经过隐身仿真、隐身测试等手段,获取了天线在不同频点、不同极化下的RCS均值,并通过仿真、测试数据对比,验证了隐身改进设计的有效性,并为其他外露物隐身设计提供了设计依据和手段.     

舰艇的雷达散射特性对反舰导弹捕捉概率的影响分析

通过对舰艇有效散射截面计算方法的引入,得出弹上雷达在不同目标特性下对舰艇的探测能力及最大探测距离,进而提出雷达最大探测距离与导弹捕捉概率在俯仰、距离和航向三个通道内的函数关系,为不同舰艇的雷达散射特性对反舰导弹捕捉概率的影响研究提供理论依据．最后得出结论,对于反舰导弹而言,舰艇的雷达散射特性对雷达捕捉概率的大小有着重大的影响,寻求舰艇的目标特性与导弹捕捉概率之间的关系值得研究．     

基于体征变化修正的火控雷达RCS仿真方法

复杂目标RCS数值计算难度高,计算机资源消耗大,在实时仿真上的应用较为困难.结合空袭兵器RCS仿真的实际情况和需求,采用部件分解法建立运算模型,并用高精度算法计算其RCS,然后通过分析体征变化对RCS的影响,推演经典算法公式提取体征修正系数;使用简单的系数运算代替复杂的算法求解,进一步得出其他不同体征空袭兵器的RCS,从而减小计算量,缩短运算周期.这种方法建模简单、物理概念清晰并能满足仿真实时性要求.     

Polymer/carbon based composites as electromagnetic interference (EMI) shielding materials

The extensive development of electronic systems and telecommunications has lead to major concerns regarding electromagnetic pollution. Motivated by environmental questions and by a wide variety of applications, the quest for materials with high efficiency to mitigate electromagnetic interferences (EMI) pollution has become a mainstream field of research. This paper reviews the state-of-the-art research in the design and characterization of polymer/carbon based composites as EMI shielding materials. After a brief introduction, in Section 1, the electromagnetic theory will be briefly discussed in Section 2 setting the foundations of the strategies to be employed to design efficient EMI shielding materials. These materials will be classified in the next section by the type of carbon fillers, involving carbon black, carbon fiber, carbon nanotubes and graphene. The importance of the dispersion method into the polymer matrix (melt-blending, solution processing, etc.) on the final material properties will be discussed. The combination of carbon fillers with other constituents such as metallic nanoparticles or conductive polymers will be the topic of Section 4. The final section will address advanced complex architectures that are currently studied to improve the performances of EMI materials and, in some cases, to impart additional properties such as thermal management and mechanical resistance. In all these studies, we will discuss the efficiency of the composites/devices to absorb and/or reflect the EMI radiation.     

In vitro attenuation of acrolein-induced toxicity by phloretin, a phenolic compound from apple

In the current study, the protective effects of phloretin were investigated in acrolein-challenged amino acid, protein, and cell models. It was found that the formation of FDP-lysine (a typical acrolein-lysine adduct) was strongly inhibited in the presence of phloretin and the remaining electrophilic site in FDP-lysine was also blocked by phloretin. Moreover, direct trapping of acrolein by phloretin was found to be responsible for inhibiting the incorporation of carbonyl groups into BSA and oligomerisation in RNase A. Subsequently, the reduction of LDH release in human neuroblastoma SH-SY5Y cells under acrolein challenge suggested the cytoprotective effects of phloretin. Such protection might be mediated through inhibiting the increased cellular protein carbonyl level as revealed by Western blotting analysis. The present study highlighted an apple phenolic compound, phloretin as a promising candidate in prevention or treatment of acrolein-associated human diseases.     

利用复射线法分析腔体的散射场

利用基于几何光学和高斯波束法的复射线法分析了相对任意开口圆柱腔的后向散射场。该圆柱腔内部包含较复杂的中心锥，叶片等结构，计算了两种较复杂进气道模型的雷达截面，所得结果均与弹跳射线法结果进行了比较，二者吻合很好，该方法受计算机内存影响小，对电大腔体，复射线法精确高效。     

Thermal fatigue estimation due to thermal stratification in the RCS branch line using one-way FSI scheme

The scheme and procedure for thermal fatigue estimation of a thermally stratified branch line were developed. One-way FSI (fluid and structure interaction) scheme was applied to evaluate the thermal stratification piping. Thermal flow analysis, stress analysis and fatigue estimation were performed in serial order. Finally, detailed monitoring locations and mitigation scheme for the integrity maintenance of piping were recommended. All wall mesh and transient temperature distribution data obtained from the CFD (computational fluid dynamics) analysis were directly imported into the input data of stress analysis model without any calculation for heat transfer coefficients. Cumulated usage factors for fatigue effect review with nodes were calculated. A modified method that combines ASME Section III, NB-3600 with NB-3200 was used because the previous method cannot consider the thermal stratification stress intensity. As the results of evaluation, the SCS (shutdown cooling system) line, branch piping of the RCS (reactor coolant system) line, shows that the CUF (cumulative usage factor) value exceeds 1.0, ASME Code limit, in case thermal stratification load is included. The HPSI (high pressure safety injection) line, re-branch piping, shows that temperature difference between top and bottom of piping exceeds the criterion temperature, 28°C, and that the CUF value exceeds 1.0. Therefore, these branch pipings require a detailed review, monitoring or analysis. In particular, it is recommended that the HPSI piping should be shifted backward to decrease the influence of turbulent penetration intensity from the RCS piping. This paper was recommended for publication in revised form by Associate Editor Jae Young Lee Kwang-Chu Kim received his B.S., M.S. and Ph.D degrees from department of mechanical engineering, Kyunghee University in 1993, 1995 and 2000, respectively. He has worked for Korea Power Engineering Company since 1995 and he is now a senior researcher. Dr. Kim’s research area includes CFD analysis, flow control, plant design and simulator. Jong-Han Lim received his B.S. degree from department of mechanical engineering, Chosun University in 1981, M.S. and Ph.D degrees from department of mechanical engineering, Kyunghee University in 1986 and 1992, respectively. He worked for Hyundai Motors Company during 1986-95. He is now a professor in department of mechanical & automotive engineering, Kyungwon University. Dr. Lim’s research interests are in the area of thermal flow, internal combustion and liquid atomization. Jun-Kyu Yoon received his B.S. degree from department of mechanical engineering, Chosun University in 1981, M.S. degree from department of mechanical engineering, Kyunghee University in 1987 and Ph.D degree from department of mechanical engineering, Myongji University in 2001. He worked for Hyundai Motors Company and Asia Motors Company during 1985–96. He is now a professor in department of mechanical & automotive engineering, Kyungwon University. Dr. Yoon’s research interests are in the area of flow control, heat transfer, liquid atomization, spray and combustion.     

主动雷达制导反舰导弹攻击目标计算

为了准确表述主动雷达制导反舰导弹的捕捉性能，通过对导弹实际捕捉动作的分析，给出了导弹门限雷达截面的概念和计算公式，并按目标幅起伏特性和现代战场的实际，加权修正美国海军研究室给出的目标雷达截面计算公式，探讨了反舰导弹可攻目标的计算和判断问题，为导弹可攻目标的表述和导弹作战使用提供了依据．     

福岛第一核电厂2号机组严重事故进程模拟分析

本文应用MELCOR程序,通过建立全厂详细的模型,对福岛第一核电厂2号机组在地震发生后4天(96h)内的严重事故进程进行了模拟分析并与电厂实测数据进行了比较。基于文中假设的模拟计算得到的趋势与电厂现有实测数据较为一致,分析结果表明:假设TORUS隔间内海水淹没一半时,作为新增的外部热阱与RCIC系统耦合工作,可有效地将堆芯衰变热排出,并延缓了安全壳压力上升。96h内安全壳压力未达到过滤排放系统开启值;RCIC系统在事故发生后近3天失效,此后4.6h操纵员通过开启主蒸汽泄压阀(SRV)对反应堆进行快速卸压,然而堆芯在消防水注入时接近完全裸露,继而发生强烈锆水反应;6h内产氢量达到近800kg。事故后期堆芯通道依然维持可冷却几何形状,最终操纵员通过开启第2组泄压阀对反应堆进行卸压,消防水泵得以有效向反应堆注入冷却水,堆芯重新淹没并冷却。     

飞航导弹雷达截面(RCS)计算

综合应用扩展物理光学法、等效电磁流法和几何光学法等高频ＲＣＳ分析方法,计算飞航导弹各散射中心的ＲＣＳ;考虑目标各部分散射场间的相对相位关系,计算导弹整体ＲＣＳ,计算结果与相关文献结论吻合较好,可满足工程分析的需要。